Five routes to air for a borewell rig
A borewell or DTH rig needs a compressor that matches its hammer, hole diameter and depth. Typical borewell machines deliver 600–1,500 cfm at 200–400 psig (13.8–27.6 bar), with special units up to 35 bar (507.6 psig). There are five ways to put that air on site, and they can be combined.
| Route | Best suited to | Main trade-off |
|---|---|---|
| New compressor | Owners with steady, year-round drilling and a clear duty for years ahead | Highest capital outlay; you carry maintenance and utilisation risk |
| Used or refurbished compressor | Owners who need to own but want a lower entry cost | Condition and history must be verified; parts availability must be checked |
| Rental or hire | Seasonal work, a single project, trial of a larger class, or cover during repair | Ongoing hire charge; machine returns when the job ends |
| Repair or service | An owned machine that is basically sound but underperforming or stopped | Rig downtime during diagnosis and repair |
| Overhaul or reconditioning | An older machine with a sound structure and worn airend, engine or coolers | Workshop time; scope depends on what is found on inspection |
Start with the drilling duty, not the machine
Every route begins with the same question: what air does the work need? Buying by cfm alone is a common mistake. A compressor must supply enough flow to clear cuttings from the hole and enough pressure to drive the hammer and lift the water column at the depth you drill.
- Hammer and bit: the hammer maker’s air consumption at the working pressure sets the minimum flow and pressure.
- Hole diameter and drill pipe size: together they set the annular space and therefore the up-hole velocity needed to lift cuttings.
- Depth and water ingress: deeper and wetter holes demand more pressure to start and keep the hammer working against the water column.
- Ground: hard rock, fractured zones and clay-rich overburden behave differently and affect both penetration and flushing.
- Site: high summer ambient, dust and altitude reduce the margin a machine has in reserve.
Once the duty is clear, the route becomes a commercial and practical decision rather than a guess.
When does buying a new compressor make sense?
New makes sense when the rig works most of the year, the duty is stable and the owner wants full control of maintenance and availability. A new machine starts with known condition, full documentation and the latest design. The owner should still plan the lifecycle from day one: service intervals, a stock of filters and separator elements, and a logbook. We supply new borewell compressors of several brands and, for long-term projects, can supply brand-new machines to site.
Is a used or refurbished compressor a sensible buy?
A good used machine can deliver years of drilling at a lower entry cost, but only if it is assessed properly. Before buying, check:
- Nameplate data: make, model, serial number, rated pressure and flow.
- Running hours and any available service history.
- Output at working pressure and normal engine speed.
- Discharge temperature under load on a typical day.
- Oil carry-over, leaks and the condition of the separator and coolers.
- Engine condition: starting, smoke, oil pressure and blow-by.
- Chassis, canopy, axle and towing gear for corrosion and damage.
- Availability of airend and engine parts for that model.
We sell used and refurbished borewell compressors and tell buyers plainly what has been done and what has not.
When is hiring the better choice?
Hiring suits work that is seasonal, project-based or uncertain. It also suits owners who want to test a larger pressure class before buying, or who need to keep drilling while their own compressor is in the workshop. Our own rental fleet covers 50–2,000 cfm and 2–30 bar (29–435.1 psig), which includes diesel portables and high-pressure units. On hire jobs our team changes oil and services the machine every 300 running hours, and operators can be arranged where needed.
Repair, overhaul or recondition an owned machine?
| Condition found | Likely route | What we check first |
|---|---|---|
| One failed component: sensor, valve, belt, hose | Repair | Fault history, safety shutdown logic, the failed part’s markings |
| Rising temperature, falling output, clean filters | Service plus diagnosis; possibly cooler restoration | Cooler fouling, oil condition, thermostatic valve, separator pressure drop |
| Airend noise, metal in oil, persistent low output | Airend overhaul | Bearing condition, rotor clearances, oil analysis where available |
| Engine smoke, low oil pressure, hard starting | Engine overhaul | Compression, injection, cooling and lubrication systems |
| Several systems worn but structure sound | Reconditioning | Chassis, canopy, parts availability, the owner’s future duty |
Specialist processes such as airend rotor work are arranged where needed. A hired machine can cover the rig while the work is done.
A simple way to compare the routes
Put each route on the same footing before deciding. Estimate the drilling hours you expect over the next two or three seasons. For each route, list the cost of getting air on site, fuel, maintenance and parts, expected downtime and what the machine is worth at the end. Include the cost of an idle rig and crew for each day lost. That last item often decides the matter: a cheaper route that leaves the rig standing for a week can cost more than a dearer route that keeps it drilling.
Our rental versus ownership calculator explains the method in more detail.
Spare parts for every route
Whatever the route, spares keep the rig working. We identify parts from the nameplate, the old part and the machine’s history, and confirm fit before quoting. We say whether a part is genuine or a quality aftermarket equivalent. For high-pressure airend and separator parts we normally recommend genuine or an exactly matched specification.
Common mistakes when choosing a route
- Buying on price alone: a cheap used machine with an unknown airend history can cost more in the first season than a fairly priced, assessed one.
- Undersizing to save fuel: a compressor that cannot hold pressure at depth slows penetration, leaves cuttings in the hole and raises the risk of a stuck hammer. Fuel per metre, not fuel per hour, is the figure that matters.
- Repairing without diagnosis: changing parts until the fault goes away wastes money and time. Readings of pressure, temperature and output point to the real cause.
- Ignoring parts availability: before buying any used or older model, confirm that airend, engine and separator parts can still be sourced.
- Leaving hire too late: arranging a standby or repair-cover machine before the drilling season starts is easier than finding one after a breakdown.
- No logbook: without running hours and readings, every later decision, from overhaul timing to resale, becomes guesswork.
Avoiding these mistakes usually matters more than the choice between routes. A well-assessed used machine, a correctly sized hire unit or a planned overhaul can each be the right answer for a given rig and season, provided the duty is clear and the machine’s condition is known.
High summer ambient temperatures across Telangana and Andhra Pradesh deserve special attention. Whatever the route, confirm that the machine is designed for the heat and dust it will meet, and that coolers will be cleaned regularly during the season.
How Reddy Compressors helps
We supply all types, all brands and all models of borewell compressors: new sales, used and refurbished machines, rentals, service and spare parts. We are an independent multi-brand specialist working with ELGi, Atlas Copco, Ingersoll Rand, KAESER, Chicago Pneumatic, Doosan and others; we are not an authorised dealer, and brand names belong to their owners. We have tie-ups with all major and reputed brands.
- Help defining the drilling duty before you choose a route.
- New and used machines, with plain condition reports on used equipment.
- Hire from our own fleet, including high-pressure units, with service every 300 running hours on hire.
- Service, repair, overhaul and reconditioning by more than 20 service engineers and technicians across Telangana and Andhra Pradesh.
- Machines, rentals and spare parts supplied across India.
We have worked since 2002 from Srinilayam, 12-13-200, First Floor, Street No. 1, Tarnaka, Secunderabad 500017. Phone +91 99590 60718 or +91 92468 88812.
What to send us
- The route you are considering, or “not sure yet”.
- Rig type, hammer size, hole diameter and typical depth.
- Working pressure and flow you use now, if known.
- For an owned machine: make, model, serial number, nameplate photo, running hours and symptoms.
- Site location, start date and expected duration of work.
Frequently asked questions
Should I buy or rent a borewell compressor?
Buy when your rig drills most of the year with a stable duty and you can manage maintenance. Rent when work is seasonal, project-based or uncertain, or when you want to cover a repair. Compare both on the same basis: drilling hours expected, running and maintenance costs, downtime and residual value. The cost of an idle rig often decides the answer.
What size compressor do I need for a borewell rig?
It depends on hammer size, hole diameter, drill pipe, depth and water ingress. Typical borewell compressors deliver 600–1,500 cfm at 200–400 psig (13.8–27.6 bar), with special units up to 35 bar. Start from the hammer maker’s air consumption at working pressure, then check up-hole velocity and the pressure needed at your deepest wet holes.
Is a used borewell compressor reliable?
It can be, if its condition is checked properly. Verify output at working pressure, discharge temperature, oil carry-over, engine condition, chassis and the availability of parts for that model. Ask for running hours and any service records. We sell used and refurbished machines and explain clearly what has been inspected, repaired or replaced before sale.
Can I get a hired compressor while my machine is being repaired?
Yes, subject to availability in our own rental fleet. Many owners hire a high-pressure compressor so the rig keeps drilling while their machine is in the workshop. Tell us the pressure and flow class, the site and the expected repair time, and we will confirm a suitable machine and the hire arrangement.
Do you work on all brands of borewell compressor?
Yes. We sell, rent, service and supply parts for borewell compressors from ELGi, Atlas Copco, Ingersoll Rand, KAESER, Chicago Pneumatic, Doosan and other makers. We are an independent multi-brand specialist, not an authorised dealer of any brand. Parts are identified from the nameplate and confirmed for fit before we quote.
Do you support borewell contractors outside Telangana?
Yes. Our service teams cover all of Telangana and Andhra Pradesh, and we supply compressors, rentals and spare parts across India. For projects elsewhere, we discuss site support case by case where it is feasible. Our only office is at Tarnaka, Secunderabad.
Related pages
Calculators and worked examples
These tools give indicative figures for screening, comparison and for preparing an enquiry. They run in your browser and send nothing. No prices or tariffs are assumed: enter your own to see costs. Efficiencies and other figures shown are example values: replace them with your own. Results are not a performance guarantee or a design certificate; final selection is confirmed by a service engineer against the machine data sheet and the site.
Rental versus ownership
Find the point at which owning a compressor costs less than hiring one for the same duty.
The worked example below shows the method with fixed numbers. Turn on JavaScript to change the inputs.
Worked example
Inputs
- Months of need: 18
Result
- Result: Enter your own prices above (purchase price and monthly hire charge are needed; no prices are assumed)
Method. Rental total = monthly hire × months + fuel/power. Ownership total = purchase price + running cost × months + service. Break-even month = (purchase) ÷ (monthly hire + monthly rental running − monthly ownership running). All prices are entered by you; none is a quotation.
What to take from it. The answer depends on how long the need really lasts. Below the break-even hire is cheaper; beyond it ownership usually is.
Technical content reviewed by D. Srinivas Reddy, Managing Partner and service engineer, Reddy Compressors. Last updated 17 October 2026. How our engineering content is reviewed.